This invention relates to air bag covers having decorative appliques bonded thereto.
Presently, when air bag covers are provided in automobiles on the driver""s side of the vehicle, the air bag is stored in the steering column behind an air bag cover. During automatic inflation of the air bag, the air bag cover moves away from the steering column to permit its safety function between the steering column and the operator of the vehicle.
Recent practice in the automotive industry is utilization of all plastic fabricated air bag covers. It is known in other automotive parts areas that different, aesthetically pleasing outer surfaces enhance the overall appearance of the interior of automotive vehicles. Use of decorative appliques having solid colors contrasting or blending with the different colors of the plastic air bag covers is often sought after. Simulated wood grain finishes, and metallic finishes are also popular and economically feasible in combination with various plastic automotive parts.
Difficulties are known to arise in properly applying applique films to annular or arcuate plastic outer surfaces. Applique films are usually approximately 0.5 millimeters thick or less and are therefore not easily applied directly to an outer air bag cover surface. Improper application causes small air pockets to occur on the decorative film which often makes the resultant air bag cover, unattractive and thus unusable. Additionally, conventional air bag covers invariably include annular or arcuate surfaces, and affixing the thin applique film to these designated surfaces is even more difficult.
The deposition or fastening of the applique must be perfected with a method that affords a smooth surface and neat appearance. Thus it is known to utilize a backing material or liner in conjunction with a thin applique film to afford a clean, smooth appearance of the final product.
In addition, the applique must be affixed to the front cover in such a way as to prevent the applique from separating from the front cover when the air bag explodes. The applique must therefore be bonded to the front cover with sufficient strength to prevent fragmentation of the applique during air bag inflation and exit.
The U.S. patents to Eckout U.S. Pat. Nos. 5,487,557 and 5,529,336 disclose an automotive air bag cover having a decorative applique fastened thereto. The air bag cover is manufactured from plastic and includes a front panel adapted to enclose an uninflated automotive air bag. The front panel includes inner and outer surfaces. Side panels are further provided and are connected to and extend from the front panel. The decorative applique is fastened to the outer surface of the front cover by a plurality of connecting towers which extend through the front cover. Seams are provided for permitting the air bag to inflate and exit the front cover. The decorative applique is fastened to the front cover adjacent the seams in a non-overlapping fashion such that the decorative applique does not interfere with exit or inflation of said air bag.
Typically, plastic parts are painted after they are molded. The painting process requires elaborate facilities and consequently necessitates large expenses. For instance, significant square footage of a factory must be dedicated to a clean room environment for the spraying of paint and clear coat and for the baking and curing of paint on components, such as those components used in the automotive industry, such as body panels, air bag covers, instrument panels and the like. Moreover, solvent-based paints have in recent years raised significant environmental concerns because of the volatile organic components which are emitted into the air during the application of such solvent-based paints. As a result, the evaporation of such solvents must be strictly monitored to satisfy environmental and safety regulations.
In addition, automotive components, especially interior automotive components, are strictly scrutinized following the painting process in order to match or conform the automotive component to the styling and aesthetic requirements of the associated interior trim product. Painting such automotive components following the molding process, raises quality concerns with respect to the color, consistency, and thickness of each individual paint application.
U.S. Pat. No. 4,902,557 to Rohrbacher discloses a method and apparatus for manufacturing a thermoplastic polyolefin composite useful as an exterior auto or truck body part.
U.S. Pat. No. 4,769,100, the Short reference, teaches a method of applying a carrier film pre-printed with metallic paint to an automobile body panel in a vacuum forming process.
U.S. Pat. No. 4,952,351 and U.S. Pat. No. 5,466,412, the Parker patents, teach a method of manufacturing an air bag cover for an inflatable air bag system including a bondable film carrier, which is painted after the film carrier is molded.
However, despite the above prior art there is a need to provide a xe2x80x9crichxe2x80x9d (i.e. painted, glossy) look to the front panel of an air bag cover that is easier, cheaper andxe2x80x9cgreenerxe2x80x9d to manufacture yet not interfere with exit or inflation of the air bag.
An object of the present invention is to provide an automotive air bag cover having a decorative applique bonded thereto completely about at least one flap portion of a front panel of the cover to satisfy the above need and method of making same.
In carrying out the above object and other objects of the present invention, an automotive air bag cover constructed in accordance with the present invention is provided. The air bag cover includes a plastic front panel adapted to enclose an uninflated automotive air bag and having at least one flap portion including a hinge and an edge through which the air bag exits. The front panel further has inner and outer surfaces. The outer surface has a receiving portion disposed adjacent to and completely about the at least one flap portion. The cover also includes a seam formed in the surface of the front panel for permitting the air bag to deploy. The seam defines the edge of the at least one flap portion of the front panel and is formed in a non-overlapping fashion with the receiving portion. The air bag cover further includes a decorative applique preform bonded to the receiving portion of the outer surface completely about the at least one flap portion in a completely non-overlapping fashion with the seam such that upon inflation or exit of the air bag, the at least one flap portion moves away from the decorative applique preform which does not detach from the front panel or interfere with the air bag.
Still further in carrying out the above object and other objects of the present invention, a method is provided for making a molded plastic automotive air bag cover having a decorative applique. The method includes the step of providing a thin film having top and bottom surfaces. The thin film is selected from the group consisting of polyester, polyurethane and polycarbonate. The method also includes the step of vacuum forming the film sheet in a mold cavity to obtain a preform. The method further includes the step of cutting the preform to form a decorative applique preform having a central aperture which extends completely therethrough. The method also includes the step of placing the decorative applique preform in a mold cavity of an injection mold having a shape defining an automotive air bag cover including a front panel with at least one flap portion. The method then includes the step of injecting a thermoplastic elastomer into the mold cavity of the injection mold to generate the rest of the air bag cover wherein the decorative applique preform is disposed adjacent to and completely about the at least one flap portion. The generation of the rest of the air bag cover creates sufficient pressure and heat to bond the rest of the air bag cover to a bottom surface of the decorative applique preform to form the molded plastic air bag cover having the decorative applique.
Yet still further in carrying out the above object and other objects of the present invention, an automotive air bag cover is provided. The cover includes a front panel for enclosing an uninflated air bag. The front cover has at least one flap portion including a hinge and an edge through which the air bag exits. The front panel has inner and outer surfaces. The outer surface has a receiving portion disposed adjacent to and completely about the at least one flap portion. A seam is formed in the surface of the front cover for permitting the air bag to deploy. The seam defines an edge of the at least one flap portion and is formed in a non-overlapping fashion with the receiving portion. The air bag cover also includes a decorative applique preform bonded to the receiving portion completely about the at least one flap portion and in a completely non-overlapping fashion with the seam such that upon exit of the air bag, the at least one flap portion moves away from the decorative applique preform which does not detach from the front panel or interfere with the air bag.
The above objects and other objects, features, and advantages of the present invention are readily apparent from the following detailed description of the best mode for carrying out the invention when taken in connection with the accompanying drawings.